Method and apparatus for punching metal sheets



April i G. J. GREINER 2,156,015

METHOD AND APPARATUS FOR PUNCHING METAL SHEETS 2 Sheets-Sheet 1 Filed April 10, 1957 April 25. 1939. I G. J. GREINER METHOD AND APPARATUS FOR PUNOHING METAL SHEETS Filed April 10, 1937 2 Sheets-Sheet 2 Patented A azs, 1939 2,156,015

UNITEDSTATES PATENT. OFFICE METHOD AND APPARATUS FOR PUNCHING. METAL snaarrs George J. Greiner, New York, N. Y., assignor to Continental Can Company Inc., New York, N. Y., acorporation of New York Application April 10, 1937, Serial No. 136,223 8 Claims. (Cl. 164 88) The present invention relates to new and useof the row containing the staggered blanks and ful improvements in a method of punching blanks the positionof themale die for this row during from metal sheets and to a multiple die or punch its idle stroke while the last blank in another row press for carrying out the method. The invention is being punched.

5 particularly relates to the simultaneous punching The invention relates generally to a method and 5 of a plurality of rows .of blanks from a metal an-apparatus for punching a plurality of rows of sheet which is fed by hand to the press. blanks from a metal sheet during a single multi- An object of the invention is to provide a methple row punching operation. The invention con- Od and apparatus for the simultaneous punching templates the use of a multiple punch or die press, not a plurality of rows of blanks from a metal one of the die members being located in advance l0 sheet wherein the blanks'in at least one of the of another so that the blanks in at least one of rows are staggered with respect to the blanks in the rows are offset with respect to the blanks in another, and wherein the die for punching the another row. The gauging mechanism for propblanks in the staggered row is prevented from erly positioning the metal sheet for each multiple contacting with the metal sheet during its idle row punching operation is of the type shown and 15 stroke while the last blank in another row is described in my prior Patent. No. 1,934,303 of being punched. a November 7, 1933. In the simultaneous punching A further object of the invention is to provide of a plurality of rows of blanks from a metal sheet a method and apparatus for a multiple row wherein the blanks-in one of the rows are stagg0 punching operation, as indicated above, wherein gered with respect to the blanks in another row, the scrap of metal at the end of the row from it has been found that the die for the row of stagwhich the relatively staggered blanks are gered blanks often contacts with the thin scrap punched, is deformed out of the path of the die of metal left at the edge of that row, because for that-row during its idle stroke while the last thesheets often vary slightly in length. When 5 blank in another row is'being punched. one of the sheets extends into the path'of the die The above and other objects of the invention for the row of staggered blanks, uneven wear and will be obvious and will be hereinafter more fully often damage results to. the cooperating dies for pointed out. this row. According to thepresent invention, the In the drawings: female die for the row of staggered blanks is pro- Fig. 1 is a side elevation of a portion ofthe vided with a spring retaining finger which, by 30 press employed for punching the blanks. proper manipulation of the hand fed sheet, is

Fig. 2 is a diagrammatic plan view showing adapted to engage the scrap of'metal left'at the the metal sheet in its initial set position on the edge of the sheet adjacent the row of staggered supporting bed of the press for punching the blanks so that it may be deformed inwardly, thus first blank in the staggered row at the beginning permitting the male. die to pass by the sheet 35 of the first multiple row punching operation. during its idle stroke. 5

Fig. 3 is a view similar to Fig. 2,.showing the' It is believed that the invention will be better metal sheet in its next set position for the slmulunderstood by referring to the illustrated emboditaneous punching of blanks from'a plurality'of ment thereof in the accompanying drawings. 40 rows during theflrst multiple row punching op- The punch press is of the type shown in my afore- 40 eration. said patent, and includes a frame ID on which is Fig. 4 is a view, similar to Fig. 2, showing the mounted a bed II for supporting the sheets S, metal sheet in its initial set position on the supto be punched. A plunger I2 is mounted on the porting bed of the press for punching the first frame- 10 and carries at the lower end thereof a blank in the staggered row at the beginning of pair of male dies l3, l4. With respect to the 46 the second multiple row punching operation. direction in which the sheet is fed, the dies l3,

Fig. 5 is a detail view, partly in section, show- H are offset and the die I3 is disposed in advance I ing the cooperating male and female dies for the of the die [4. The male dies cooperate with. fe-

7 row of staggered blanks and the improved means male dies I3a, Ila which are similarly located 5 for preventing the male die from contacting with and mounted in the bed H. The plunger I2 is 50 the metal sheet during its idle stroke. reciprocated -from' a main rotating shaft l5 Fig. 6 is a fragmentary plan view of the female mounted in the frame ID ofthe machine. The die shown in Fig. 5. supporting bed I I is provided with a pair of guides Fig. 7 is a fragmentary diagrammatic plan view l6, l1, both of which are made up in sections, as

5 showing the deformed scrap of metal at the end indicated in Figs. 2, 3 and 4. The sections of 66 from the sheet with the region or the dies where the punching operation takes place. The sheet S is placed against one of the'guides, properly positioned, and fed by hand beneath the punching head so that during the step-by-step feeding of'the sheet, a plurality of rows of blanks are simultaneously punched blanks in one rowstaggered-withrespect to the blanks in 'another row.

The sheet is positioned for punching by a gauge finger I8 and a placing finger l8 which are similar in operation and construction to the showing in my aforesaid patent, The gauge finger I8 is carried by an arm 20 which is bent at right angles intermediate its ends so thatzthe portion thereof adjacent the gauge finger extends in a direction parallel to the guides l6, II. The

gauge finger I8 is disposed in advance'of the die 13 and in line with the center of the row of blanks punched thereby. The arm 20 is supported by an oscillating shaft 2] carried by a bracket 22 which is mounted on the frame I0. is connected by a link 23 to the main rotating shaft l and is operated thereby in themanner shown and described in my aforesaid patent so that the gauge finger I8 is thus raised andlowered in timed relation with the plunger l2.

The placing finger I8 is carried by a lever 24 pivotally mounted in a bracket 25 on the under face of the supportingbed II. The finger it passes up through an opening bed II and a spring 26 operates against the lever to normally retract the finger l9 away fromthe upper surface of the supporting bed. The placing finger I9 is disposed in advance of the die I! and in line with the center of the row of blanks punched thereby. Thus, the gauge finger -I8 is in'advance of the placing finger I8 with respect to the direction in which the sheet is fed. The distance betweenthe gauge finger I8 andthe placingfinger I9 along a line parallel to the direction in which the sheet is fed, is. sub,-

stantiallyequal to the diameter of the blanks punched fiom the sheet.

The placing finger l9 is thus manually operablev to initially position the sheet for the punching of the first blank in amanner to be-hereinafter pointed out.

The female die Ha, which is located in rear of the die I3, is provided with a recess 21, as shown in Fig., 5, in line wi h the center of the row of blankspunched by the die M. A spring retaining finger 28 is secured within. the recess 21 and the upper end 280. thereof is curled in the direct'ion in which the sheet. is fed. In positioning thesheet for .the last punching operation by the die IS, the rear edge of the sheet is passed over the hooked end of the finger 28 and is then forced back into engagement with the hooked end 280. so that, in this manner, the scrap of metal remaining at. the end 'of the row from which the staggered blanks have been punched, may be deformed or bent inwardly, Fig. '7, so that it-will not extend into the path of movement of the male die l4 during its idle stroke.

The manner in which the sheet is fed and positioned for the punching operations will now be described, reference being had to Figs. 2 through'l. One edge of the sheetS is placed in the guide I! and the lever 24 is manually operated to elevate the placing finger l9 above the upper surface of the supporting bed II. The sheet S is moved forwardly in the direction of the arrow A until the front edge thereof abuts against the placing finger l8, as shown in Fig. 2. when the of the sheet for the I first blank b The arm 20 in the supporting final blank will be punched v is an idle stroke of the'die as shown in 2,156,015 v I k r.

sheet is in this position, the plunger 12 and dies l3, I are moved downwardly so that the die ll,

cooperating with !the female die Ila, punches the first blank 11? in the row H, as shown in Fig. 2. There is an idle stroke of the die I! during this punching operation,after which the lever 24 is released so that the placing finger I9 is retracted beneatnthe upp r surface? of the supporting bed H. The sheet S is then fed in the direction of the arrow A until the front edge thereof abuts against the gauge finger 18, which has been raised and lowered in timed relation with the stroke of the plunger l2. The position next punching operation is shown in Fig. 3 'wherein the die l3 punches the r g in the line b--b and the die ll punches the blank a in the line H. During the subsequent feeding of the sheet, the placing finger l9 remains inoperative and the gauge finger I8 is raised and lowered with the upward and downward stroke of the plunger I2. As the gauge finger I8 is lifted above the sheet, the operator slides the sheet along the guide l1 so that, when the gauge finger I8 is lowered again, it willdescend into the opening previously punched-by the die [3, and engage the edge of this opening for the positioning of the sheet for the next multiplerow punching operation, in the manner shown and described in my aforesaid patent. The blanks in the row a-a are designated as being staggered with respect to the blanks in the row b- -b. When the last blank in the row H has been punched, the operator slides the sheet forwardly over the spring finger 28 and then rearwardly into engagement with the hooked end 28a thereof, as shown in Fig. 5. Further movement of the sheet'in a rearward-direction against the, spring finger 28 will effect a deforming or inward bending of the scrap of metal S1 left at the end of the row 0-0. of staggered blanks, as; shown in Fig. 7.' The sheet is now positioned with. the

gauge finger IBabutting against the edge of the last opening punched in therowbbso that, upon the next down I by the die [3 from the row b-b. There l4 during this final punching operation. The

stroke of the plunger l2,'the

scrapof metal left at the end of the staggered row been deformed in the manner indicated above, is out of the path of the die H so that it will not be damaged or worn during its idle stroke. The hooked end 28a. of the spring finger 28, opening in the direction in which the sheet is fed, permits the sheet to pass thereover and to depress the same into the recess 21 as the sheet is fed, toward the punch.

At the end'of the operation, the sheet is moved rearwardly and the edge thereof placed in the guides it, as shown in Fig. 4. When the sheet is so positioned, the placing finger I9 is again elevated and the sheet moved forwardly until the front. edge thereof abuts against the placing finger. During this second multiple row punching operation, the sheet is fed and positioned by the placing finger l9 and thegauge fingerv It operates to position the sheet for each punching operation in the same manner indicated above. For the final multiple row punching operation, the sheet is reversed and the opposite edge thereof is .placed in the guide l6 and fed in the same manner. 1

It is of course to be clearly understood that more than two dies'rnay be employed, in which case the, positioning-of the sheet against the placing finger W for the initial punching operation a-a, having first multiple row punching and the subsequent positioning of the sheet by the gauge finger I! will be identical with that described above.

It is to be clearly understood that minor changes in the details of construction and arrangement of parts may be made without departing from the scope of the invention as set forth in the appended claims.

I claim:

1. A method of simultaneously punching a plurality of rows of blanks from a metal sheet with the blanks in one row staggered with respect to the blanks in another row, which consists in feeding and positioning the sheet for each punching operation, and preventing movement of the scrap of metal left at the end of the row of staggered blanks while the sheet is being fed and positioned for punching the last blank in another row whereby to prevent the scrap of metal from extending into the path of the die for the staggered row during its idle stroke.

2. A method of simultaneously punching a plurality of rows of blanks from a metal sheet with the blanks in one row staggered with respect to the blanks in another row, which consists in feeding and positioning the sheet for each punching operation, and deforming the scrap of metal left at the end of the row of staggered blanks inwardly of the sheet while positioning the sheet for punching the last blank in another row whereby to prevent the scrap of metal from extending into the path of the die for the staggered row during its idle stroke.

3. A die press for punching blanks from a metal sheet, comprising a bed for supporting the sheet to be punched, a plurality of dies arranged in offset relation for punching a plurality of rows of blanks from the sheet with the blanks in one row staggered with respect to the blanks in another row, means including guides for positioning the sheet for each punching operation, and means disposed in line with the row of staggered blanks and engageable with the scrap of metal left at the end of the staggered row for preventing the scrap of metal from extending into the path of the die for the staggered row durlng'its idle stroke.

4. A die press for punching blanks from a metal sheet, comprising a bed for supportin the sheet to be punched, a plurality of dies arranged in offset relation for punching a' plurality of rows of blanks from the metal sheet with the blanks in one row staggered with respect to the blanks in another row, means including guides for positioning the sheet for each punching operation, and means associated with the die forthe staggered row and engageable with the scrap of metal left at the end of the staggered row for preventing the scrap of metal from extending into the path of the die for the staggered row during its idle stroke.

5. A method of simultaneously punching a plurality of rows of blanks from a metal sheet with the blanks in one row staggered with respect to the blanks in another row, which consists in feeding the sheet into abutting relationship with a stop located in line with the row containing the staggered blanks for the first punching operation, then feeding the sheet into abutting relationship with a second stop in line with another row for a multiple punching operation, continuing the feeding and positioning of the sheet by said second stop, and finally deforming the scrap of metal left at the end of the row of staggered blanks prior to punching the last blank in another row whereby to prevent the sheet from extending into the path of the die for the staggered row during its idle stroke.

6. A die press for punching blanks from a metal sheet, comprising a bed for supporting the sheet to be punched, a plurality of cooperating male and female dies arranged in offset relation for punching a plurality of rows of blanks from the sheet with the blanks in one row staggered with respect to the blanks in another row, means including guides for positioning the sheet for each punching operation, and a spring retaining finger secured to the female die for the row of staggered blanks, said retaining finger having a hooked end curled in the direction in which the sheet is fed and adapted to engage the scrap of metal left at the rear edge of the sheet at the end of the row of staggered blanks when the sheet is moved rearwardly to deform the remaining scrap of metal whereby to prevent the sheet from extending into the path of the cooperating male die during its idle stroke.

7. A die press for punching blanks from a metal sheet, comprising means for supporting the sheet to be punched, a plurality of dies arranged in ofiset relation for punching a plurality of rows of blanks from the she'et with the blanks in one row staggered with respect to the blanks in another row, means for positioning the sheet for each punching operation, and means engageable with the .edge of the scrap of metal left at the end of the row of staggered blanks for deforming the same to prevent the sheet from extending into the path ofthe die for this staggered row during its idle stroke.

' 8. A die press for punching blanks from a metal sheet, comprising means for supporting the sheet to be punched, a plurality of dies arranged in offset relation for punching a plurality of rows of blanks from the staggered with respect to the blanks in another row, means for positioning the sheet for each punching operation, and means for deforming the scrap of metalleft at the end of the row of staggered blanks inwardly of the metal sheet to prevent the sheet from extending into the path of the die for this staggered row during its idle 5 stroke.

GEORGE J. GREINER.

sheet with the blanks in one row 

